Anabolic treatment for osteoporosis is a class of medications that actively build new bone, rather than simply slowing bone loss. Most osteoporosis drugs work by putting the brakes on bone breakdown. Anabolic agents take the opposite approach: they stimulate the body’s bone-forming cells to create new bone tissue, increase bone density, and repair microdamage. These medications are typically reserved for people with severe osteoporosis or a high risk of fracture.
How Anabolic Drugs Differ From Standard Treatment
Your skeleton constantly remodels itself. Specialized cells called osteoclasts break down old bone, while osteoblasts build new bone to replace it. In osteoporosis, breakdown outpaces formation, and bones gradually thin.
The most commonly prescribed osteoporosis drugs, like bisphosphonates and denosumab, are “antiresorptive.” They work by suppressing the cells that break bone down. This slows the loss but doesn’t do much to add new bone. Over time, suppressing remodeling too aggressively can even lead to an accumulation of microdamage, since old, worn-out bone isn’t being replaced.
Anabolic agents flip the equation. They ramp up the activity of bone-building cells, producing genuinely new bone and improving bone structure. The result is meaningful gains in bone mineral density (BMD) and stronger architecture, not just a slower rate of loss.
The Three Approved Anabolic Medications
Three anabolic drugs are currently approved in the United States. Each works somewhat differently, and all are given by injection.
Teriparatide (Forteo)
Teriparatide is a synthetic fragment of parathyroid hormone, the body’s natural regulator of calcium and bone metabolism. Given as a daily self-injection into the thigh or abdomen, it stimulates osteoblasts to build new bone. In clinical trials of postmenopausal women with prior vertebral fractures, teriparatide reduced the risk of new vertebral fractures by 65% and non-vertebral fractures by 53% compared to placebo. It’s especially effective in glucocorticoid-induced osteoporosis: in one head-to-head study, only 0.6% of the teriparatide group developed new vertebral fractures over 18 months, compared to 6.1% on a standard bisphosphonate.
Lifetime use is limited to two years. After that window, the bone-building effect plateaus, and treatment needs to transition to a different type of medication to maintain gains.
Abaloparatide (Tymlos)
Abaloparatide is related to a different hormone (parathyroid hormone-related protein) but has a similar bone-building effect. It’s also a daily self-injection. In the phase 3 ACTIVE trial, abaloparatide and teriparatide produced similar increases in lumbar spine BMD after 18 months, but abaloparatide led to greater gains at the total hip and femoral neck, two sites that matter most for preventing hip fractures.
When patients on abaloparatide were switched to a bisphosphonate afterward, the combined sequence reduced the risk of new vertebral fractures by 84% and non-vertebral fractures by 39% over roughly 43 months, compared to patients who received a bisphosphonate alone. Like teriparatide, the recommended treatment duration is up to two years.
Romosozumab (Evenity)
Romosozumab works differently from the other two. It’s a monoclonal antibody that blocks a protein called sclerostin, which normally acts as a brake on bone formation. By neutralizing sclerostin, romosozumab does something unique: it both increases bone-building activity and decreases bone breakdown at the same time. This dual action makes it the only anabolic agent that also has antiresorptive properties.
It’s given as a monthly injection (two shots at the same visit) for 12 months. In the FRAME trial, romosozumab reduced vertebral fracture risk by 73% compared to placebo over the first year. When patients then transitioned to denosumab for an additional two years, vertebral fracture risk remained 66% lower than in patients who started on placebo, and non-vertebral fracture risk was 21% lower.
Romosozumab carries an FDA boxed warning about cardiovascular risk. It should not be used in anyone who has had a heart attack or stroke within the previous year. For people without recent cardiovascular events, the benefit of fracture prevention generally outweighs this risk, but it’s something your prescriber will evaluate carefully.
Who Qualifies for Anabolic Treatment
Anabolic agents are not first-line therapy for everyone with osteoporosis. They’re reserved for people with severe disease or very high fracture risk. Clinical guidelines define severe osteoporosis as a bone density T-score below -3.0, or a T-score below -1.5 combined with a history of multiple vertebral fractures or other fragility fractures.
You may also be a candidate if you’ve been on a bisphosphonate or denosumab and continued to lose bone density, fractured while on treatment, or can’t tolerate standard medications. People with certain conditions, including Paget’s disease or a history of radiation therapy involving the skeleton, are generally not eligible for the parathyroid hormone-based agents (teriparatide and abaloparatide).
Why Follow-Up Treatment Is Essential
One of the most important things to understand about anabolic therapy is that it’s not a standalone treatment. The bone density gains you achieve during those one to two years will gradually erode if you simply stop without starting another medication. The bone-building window closes, and without something to preserve the new bone, resorption picks back up.
The standard approach is sequential therapy: complete a course of an anabolic agent, then transition to an antiresorptive drug like a bisphosphonate or denosumab to lock in the gains. This sequence consistently outperforms starting with an antiresorptive alone. In trial after trial, patients who built bone first with an anabolic and then maintained it with an antiresorptive had significantly fewer fractures over the long term than those who took antiresorptives from the start.
Starting with an antiresorptive and then switching to an anabolic later is less effective than the reverse sequence. If you’re at very high fracture risk, the current thinking favors starting with the anabolic agent while your bone cells are most responsive, then consolidating with an antiresorptive afterward.
What Treatment Looks Like Day to Day
For teriparatide and abaloparatide, treatment involves a small daily injection you give yourself using a prefilled pen, similar to an insulin pen. Most people inject into the thigh or lower abdomen, and the needle is short enough that the process takes only a few seconds. Common side effects include mild nausea and dizziness shortly after injection, which typically fade as your body adjusts.
Romosozumab is administered monthly by a healthcare provider, which means 12 clinic visits over the course of treatment. Each visit involves two injections. Because it’s done in a clinical setting, there’s no self-injection learning curve, but it does require a regular schedule of appointments.
All three medications require periodic monitoring of bone density and sometimes blood calcium levels. Your provider will track your progress with bone density scans and may use blood tests that measure bone turnover markers to confirm the medication is working as expected.